Hello. I'm new here. I recently bought a 1996 Polaris Sportsman 500 4x4. I want to replace the engine in it. Does the engine have to be 1996 500 Sportsman specific? Or can I use the 500 cc engine out of another Polaris ATV? What year of engine can I use before it is to new for the 1996 Sportsman?
The engine I have now has a bad cam exhaust lobe, there is oil getting by the exhaust valve guides, the bottom motor mount holes in the block are stripped and egg shaped. Those are just a few of the things I can think of right now.
I bought this machine back in November and I'm regretting it now. I would like to just replace the existing junk engine I have with a different one. It would probably cost as much, or more to get this engine rebuilt right?
Sorry about the long post.

 

ANY Sportsman or Magnum 500 engine would work.Better if you can find a 2001 and later(HO engine) that already has the updated cam. Even if you don't want to find a 40mm carb for it to make it a true HO engine,you can use your intake manifold and 34mm carb from your 96. Cams aren't that hard to replace,but if it has other issues then an engine replacement might be a better way to go.

 

If the bottom end of the engine is good, then the CAM swap will only be about $200.

My understanding is that most 500s can be swapped from most models 96-02. Probably even newer ones.
The issues that you will run into is the wiring from the Magneto to the Bike.
The connectors changed a little over the years. But wiring is still the same.
If you don't have an issue with swapping the the Mag or CDI or just butt splicing to match the color codes, then everything else should be direct swap.
You will also need to watch out for the Carbs as well. The 99+ scrams and HO's had a larger carbs.
Not sure what the performance would be if you stayed with the smaller carb on an HO. maybe even rejet the old one?

I have rebuilt a 99 scram, 96 and 02 sportsman's.. All parts are almost a direct swap.

I'm sure someone with more experience will chime in on other items that might need changing or a better list of engines to go with.

 

You can use the ignition system from the 96 with no changes. Just an engine swap.

 

Thank you for the replies. I am going to shop around for a replacement newer model HO engine. I'm not even going to bother with the engine that's in there now. I want to have it ready for state trail riding in April or May. Thanks again guys.

 

I just wanted to post some pictures of the stuff i'm dealing with on this Sportsman.

If you look close at the picture of the rocker arm assembly, you will see the little bolt that holds the rocker shaft in place, is loose, and ready to fall out. I found it like that, when I took the valve cover off to insect the cam.
The starter switch harness is all chewed to hell by mice.
I took a picture of the recoil housing to show all the chips and cracks in it. They didnt show up though. It looks like the pull cord assembly exploded inside there and tore everything up. I pulled the flywheel and there was metal shavings all over the magnets and stator. Luckily the transmission and the rest of the Sportsman are in good shape (so far). I've got my work cut out for me on this one.

 

Sounds about like what happened an 01 Scrambler 500 4x4 I had a couple years ago. Pieces of the pull start came apart inside the housing and tore up the stator. I ended up just getting rid of it as the cost to fix it was almost as much as it was worth. There was something wrong with the transmission too when I shifted into reverse, it would clunk the whole time but it would still engage. I usually just avoided using reverse unless it was completely unavoidable. I just put it in neutral and pushed it. The engine still ran great though you couldn't start it. I ended up selling it not running for $250.

 

You can get aftermarket recoils fairly cheap now along with cheap Caltric stators if needed.Stator Fits Polaris 3086984 | eBay http://www.ebay.com/itm/like/181266412561?ul_noapp=true&chn=ps&lpid=82One thing about mice is that they're not prejudiced,they'll eat any wire no matter what color. They love that plastic..
The bolt on the left block is to lock the rocker shaft,keep it from moving side to side. Would gum up the works if it came loose and got lodged,but sounds like you have other problems to deal with also.